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In present study, X-ray diffraction and local electron probe microanalysis are used to identify microstructural and phase features of as-cast (Sm,Zr)(Co,Cu,Fe)z alloys used for manufacturing high-coercivity permanent magnets. The structure of the as-cast alloys, which were prepared in the wide composition range corresponding to the coexistence of the 2:17 and 1:5 phases, is studied in detail. The 2:17R, 1:7H, 1:5H, 5:19R, 2:7R, 2:7H, 1:3R, and 1:3H phases were identified and are shown to be simultaneously present in the as-cast state owing to the nonequilibrium phase transformations occurred upon solidification of the ingots. [ABSTRACT FROM AUTHOR]

We show here that palladium-lutetium foil Pd–11.2 wt % Lu membrane can be efficiently used for hydrogen separation via its diffusion at temperatures 300–500°С. Several correlations of the membrane structure morphology and the specific permeability of the membranes are considered. Particular attention is placed in analysis of the membrane surface studied by atomic force microscopy using the phase contrast mode. The studies performed are addressed the problem of the membrane durability for the cyclic operation up to 40 h in hydrogen atmosphere. [ABSTRACT FROM AUTHOR]

(Sm,Zr)(Co,Cu,Fe)6.0–6.8 alloys are prepared by vacuum induction melting and subsequently subjected to heat treatment in order to form a high-coercivity state, which includes annealing at 1160–1180°C for 5 h, quenching to room temperature, isothermal aging at 800°C for 20 h, and subsequent stepped tempering from 800 to 400°C at an average cooling rate of 100°C/h. The morphology and composition of main structural constituents of the alloys are studied by electron microscopy using samples in the form of individual grains separated from ingots. The hysteretic properties of the (Sm,Zr)(Co,Cu,Fe)z samples in the high-coercivity state are shown to correlate with the volume fractions of their main structural constituents, which, in turn, are controlled by the ratio of the 4f-/4d-/3d-element contents in the chemical composition of the alloy. [ABSTRACT FROM AUTHOR]